In the field of packaging food and non-food liquid and/or flowable food and non-food products, a convenient method of packaging such products in thermoplastic film has been developed and is generally known as a form/fill/seal process. In such a process a tube is formed from thermoplastic film and the bottom end seal is made by transversely sealing across the tube with heated seal bars to form a conveniently wide heat seal and, consequently, producing a bag or pouch ready to receive a product. After the heat seal is made, the bag or pouch is filled and then another transverse heat seal is made across the width of the tube in a relatively wide band. After cooling, this seal is transversely severed to separate the filled bag from the next bag to be filled. Thus, one wide band seal serves as the bottom seal for one bag and the top seal for another.
Many horizontal and vertical form/fill/seal systems are commercially available from manufacturers or suppliers such as Hayssen, Omori, Ilapak, and Kartridge Pak.
One commercial system is supplied by W.R. Grace & Co.-Conn. through its Cryovac Division. This system is referred to as Onpack (TM) and is generally described in U.S. Pat. No. 4,506,494, incorporated herein by reference, which issued on Mar. 26, 1985 to Mamoru Shimoyama et al. In the Shimoyama et al. patent a vertically held tube with a bottom end that has been closed by a transverse heat seal is filled with a liquid, semiliquid, or paste charge or contents and squeeze rollers spaced apart and above the bottom end seal squeeze the filled tube and pinch the walls of the flatted tube together. When a length of tubing of the desired height of the bag has been fed through the squeeze rollers a heat seal is made transversely across the flattened tubing by heat seal bars which clamp and seal the film of the tube therebetween. After the seal bars have been withdrawn the film moves downwardly to be contacted by cooled clamping and severing bars which clamp the film therebetween and are provided with a cutting knife to sever the sealed film at about the midpoint of the seal so that approximately half of the seal will be on the upper part of a tube and the other half on the lower. When the sealing and severing operation is complete, the squeeze rollers are separated to allow a new charge of product to enter the flattened tube after which the aforementioned described process is repeated thus continuously producing vertical form/fill/seal pouchs which have a bottom end and top end heat seal closure.
U.S. Pat. No. 4,603,793 (Stern), incorporated herein by reference in its entirety, discloses a coupling means 6a which is mounted on the inside wall of a pouch. Such coupling means, or fitments, offer several advantages in packaging food products, such as the capability of connecting the fitment to a pumping device. This permits the contents of the package to be dispensed in a controllable way. The particular coupling device described in U.S. Pat. No. 4,603,793 is mounted inside the pouch. This arrangement avoids the disadvantages associated with externally mounted fitments. These include the difficulty of properly packing multiple pouch units, and the possibility that an external fitment will be damaged during handling/storage. If this happens, the food or other pouch contents can possibly leak out.
Packaging systems combining the Onpack (TM) system with the fitment technology of U.S. Pat. No. 4,603,793 have proven effective in providing a pouch making system where the pouch, containing a food product, includes an internal fitment.
One of the requirements of using fitments of this general type is that they be accurately indexed and positioned to ensure that each fitment in a series of fitments is attached squarely to the film or pouch material at the appropriate location, for example by heat sealing the film to the fitment. If the fitments are not positioned accurately and consistently, they may not attach properly, and the resulting pouch or other container made from the film can possibly leak at the point where the fitment is joined to the film. In addition, inconsistent placement of the fitments with respect to the means for attaching (e.g. heat sealing means) and film can result in inconsistent attachment of a series of fitments on respective containers made from the film. Thus, for example, from pouch to pouch in a production run, the fitment on a given pouch may be located at a slightly different relative location on the pouch than another fitment on another successive pouch in the series. The present invention offers an improved apparatus and process for positioning and attaching fitments to a film, bag or pouch, especially in a form/fill/seal packaging system.